Combination reciprocating and rotary spray tube for a dishwasher



Oct. 31, 1961 J. JACOBS COMBINATION RECIPROCATING AND ROTARY SPRAY TUBE FOR A DISHWASHER Filed March 50, 1959 VVIII/V awa n ma We 0 WJ m H119 AI ney United States Patent 3,006,557 COMBINATION RECIPROCATING AND ROTARY SPRAY TUBE FOR A DISHWASHER James Jacobs, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Mar. 30, 1959, Ser. No. 802,909 3 Claims. (Cl. 239227) This invention relates to a domestic appliance and more particularly to an improved spray tube for a washing appliance.

In the dishwashing art it has been a primary goal of the design engineers to secure the most complete spray coverage of dishes and utensils being washed. In the past it has been conventional to design a spray device with a fixed configuration to produce the spray pattern thought best for the particular operation. However in such an arrangement no provision exists for altering this spray pattern during operation of the spray device.

Accordingly it is an object of this invention to provide a dishwasher with a spray tube device having a continuously changing spray pattern.

It is also an object of this invention to provide a spray tube with means for simultaneously rotating and longitudinally reciprocating the spray tube.

Another object of this invention is to provide a rotatably mounted spray tube with means for reciprocating the spray tube during the rotation thereof.

A more specific object of this invention is to provide a first movable magnetic means attached for rotation with a spray tube and a spray tube support having a second fixed magnetic means in juxtaposition to said first magnetic means whereby reciprocation of said spray tube may be facilitated during rotation thereof.

A more general object of this invention is to provide a dishwasher having a rotatable spray tube with magnetic means for imparting a non-rotary motion to said spray tube.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

FIGURE 1 is a schematic representation of a dishwasher adapted to include this invention;

FIGURE 2 is a fragmentary sectional view of the spray tube device of this invention with the spray tube in one of its positions;

FIGURE 3 is a fragmentary sectional view of the spray tube of this invention with the spray tube in another of its positions; and

FIGURE 4 is an elevational view of a ceramic magnet mounting arrangement taken along line 4-4 of FIG- URE 2.

In accordance with this invention and with reference to FIGURE 1 a dishwasher is provided with a rear wall 12, a top wall 14 and a sump wall 16 defining a dishwashing chamber 18. Closing the front opening 20 of the dishwashing chamber 18 is a horizontally pivoted access door 22. Within the dishwashing chamber 18 is a spray tube shown generally at 24 rotatably mounted at an inner open end 26 on a swirl inducing spray header 28. Attached to the rear wall 12 of the dishwasher 10 or to any fixed portion of the dishwasher is a support bracket or rod 30 which extends outwardly from the rear wall 12 and supports a pin 32 on which an outer closed end 34 of the spray tube 24 is journalled. Connecting the sump 16 to the spray tube 24 is a pump 36 driven by a motor 38. The pump may direct water selectively from the sump 16 by means of a conduit 40 3,006,557 Patented Oct. 31, 1961 to the swirl inducing spray header 28 or to a drain 42. For filling the sump 16 a water supply valve 44 may be included. The drying portion of a washing cycle is facilitated by the addition of a heater 46 which is selectively energized during certain parts of the Washing cycle as regulated by a conventional timer 45. A pair of utensil or dish supporting racks 48 are disposed within the dishwashing chamber 18 in a manner to expose the dishes and utensils to be washed to the maximum effect of the spray pattern issuing from slots 50 in the spray tube 24. In accordance with prior art designs such as shown in Abresch et al. 2,808,063 issued October 1, 1957, the spray pattern of the fluid being pumped from the spray tube slots 50 is unchanging, i.e. fixed by the design of the spray tube. This invention proposes to alter this spray pattern in a novel manner as will be explained more fully next following.

With reference to FIGURE 2 the spray tube 24 is comprised of a cylindrical tube portion 52 having a closed front end wall 54 at the front end 34 thereof and an inlet opening 56 in the rear end 26 thereof. The swirl inducing means or spray header 28, which is utilized to impart a rotational or spiralling motion to fluid being pumped upwardly in conduit 40, includes a cylindrical outlet portion or flange 58 and an inlet opening portion 60. Between the inlet 60 and the outlet 58 a plurality of vanes 62 are arranged generally radially between the outer housing of the spray header and an inner bearing support section 64. The housing or spray header 28 may be of any moldable material such as phenolic and may be designed with the vanes 62 or in accordance with the housing configuration teachings of my copending application. It should be understood that any means by which a swirl or rotary or spiralling motion is imparted to fluid entering the spray tube 24 through its inlet opening 56 will be suitable for use with the teachings of this invention. In this regard the aforementioned patent to Abresch et al. teaches a fluid distribution system where the spray tube is rotated in response to the swirling effect of the fluid pumped therethrough.

The manner in which the spray tube 24 is rotatably supported at its rear end 26 is as follows. The spray tube housing or header 28 has a center bearing support portion 64 in which a bearing 68 is securely positioned as by a spline arrangement or by cementing. The bearing 68 has an elongated cylindrical slot or pocket 70 for journalling and reciprocatingly supporting a pin or shaft 72. This shaft 72 is carried on a support spider 74 which is press-fit onto a shoulder 76 in the inlet 56 of the spray tube 24. The spider 74 is formed with several radially extending arms which support and centrally locate the spray tube inlet opening 56 in circumscribing relationship to the outlet flange or collar 58 of the spray head 28. These vanes do not restrict the water flowing through the spider 74 toward the outer end wall 54 of the spray tube 24 in any substantial manner. Consequently any swirl or rotary motion imparted to the water while passing through the spray header 28 will be effective to produce spray tube rotation.

The outer end of the spray tube 24 is carried on a support bracket or rod 35 which has a plate 80 aifixed thereto. In the central portion of the plate 80 is a tapped cylindrical boss 82 into which a threaded portion 84 of the shaft 32 may be threadedly fitted. On one end of the shaft 32 is a pivot or bearing portion 86 on which the spray tube 24 is journalled. Also afiixed to the support bracket 30 is a magnet 83, which may be of the ceramic type having a plurality of poles formed thereon. A similar type magnet 90 is affixed to the end wall 54 of the spray tube 24, the magnet 90 having an insert portion 92 which is secured into a molded pocket 94 in the end wall 54 of the spray tube. For providing a bearing surface for the rotatable support portion 86 of the shaft 84, a bearing 96 of graphite or other suitable material is carried within a center hole 95 of the magnet 90. The rotatable support portion 86 is adjustable longitudinally of the spray tube 94 by an adjusting knob 98. In this manner the reciprocating stroke of the spray tube 24 may be varied.

In operation water is introduced to the sump 16 through water inlet valve 44. The pump 36 is energized and water or washing fluid is directed through conduit 40 to the swirl inducing spray header 28. This swirling or spiralling water is then impelled into the spray tube 24 through the inlet opening 56 thereto. The swirling or rotary motion of the water as indicated by flow arrows 100 causes the spray tube 24 to be rotated by the frictional drag between water and spray tube.

As the spray tube 24 rotates magnet 90 rotates therewith and is caused to rotate relative to the fixed magnet 88. This brings a north pole of the magnet 90 opposite a south pole of the magnet 88 and then a south pole of the magnet 90 opposite a south pole of the mag net 88. Since it is well known that like poles of a magnet repel and unlike poles attract, the magnets 88 and 90 will be alternately repelled and attracted to each other. As shown in FIGURE 2 a north pole of magnet 90 is opposite a south pole of magnet 88 and the spray tube 24 is pulled toward the support plate 80. In FIG- URE 3 however, the continued pumping of swirling fluid to the spray tube will have caused a south pole of magnet 90 to lie opposite a south pole of magnet 88. This positioning will cause the magnets 88 and 90 to repel each other and the spray tube 24 will be forced rearwardly toward the spray header 28. It has been found that a reciprocating movement of approximately inch is satisfactory in providing a complete coverage of dishes in baskets 48 by the spray jets issuing from slots 50. This movement is predetermined by the distance between pin 86 and the rear wall 73 of the bearing 68. However, it is possible to utilize adjusting knob 98 to obtain the amount of horizontal reciprocation desired. It should be noted, of course, that the size of the slot 97 in the bearing 96 must accommodate fully the amount of horizontal movement that the spray tube 24 can traverse with the pin 86 in the slot 97. a

It should now be seen that an improved spray device has been invented which will cause a spray tube to move back and forth in a reciprocating manner at the same time that it is being rotated. This combination pulsating and rotating motion in a spray tube has been found to provide an improved cleansing result in a dishwasher.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. A fluid spray device comprising, a hollow rotatable member having an open end and radial slots, support means for journalling said rotatable member including a swirl inducing header in communication with said open end adapted to impart a swirl to fluid entering said open end for rotating said member by the frictional drag between said fluid and said member, said support means having first magnetic means affixed thereto, said rotatable member having second magnetic means for cooperating with said first magnetic means, whereby said rotatable member is caused to reciprocate repeatedly during rotation of said rotatable member.

2. A fluid spray device comprising, a cylindrical walled fluid distributing means having an open end, a closed end and radial slots in the cylindrical wall between said ends, a pivot shaft in said open end, first support means for rotatably supporting said fluid distributing means at said closed end thereof, second support means for rotatably supporting said fluid distributing means at said open end thereof and having an elongated bearing for receiving said shaft, and a swirl inducing header in communication with said open end and having vane means supportingly connected to said second support means adapted to impart a swirl to fluid entering said open end for rotating said distributing means by the frictional drag between said fluid and said distributing means before said fluid exhausts from said slots, one of said support means having magnetic means aflixed thereto, said fluid distributing means having a second magnetic means'rotatable therewith in spaced juxtaposition to said first magnetic means, whereby said pivot shaft is reciprocated repeatedly in said elongated bearing during rotation of said fluid distributing means.

3. A fluid spray device comprising, a cylindrical walled fluid distributing means having an open end, a closed end and radial slots in the cylindrical wall bet-ween said ends, a pivot shaft in said open end, first support means for rotatably supporting said fluid distributing means at said closed end thereof, second support means for rotatably supporting said fluid distributing means at said open end thereof and having an elongated bearing for receiving said shaft, a swirl inducing means in communication with said open end and having vane means adapted to impart a swirl to fluid entering said open end for rotating said distributing means by the frictional drag between said fluid and said distributing means before said fluid exhausts from said slots, fixed magnetic means having a north pole on said first support means, and rotatable magnetic means having a north and south pole attached to the closed'end of said distributing means, whereby said north pole on said fixed magnetic means is brought sequentially into juxtaposition with said north and south poles of said rotatable magnetic means to reciprocate said distributing means axially when fluid is swirlingly entering said open end.

References Cited in the file of this patent UNITED STATES PATENTS 1,882,439 Murphy Oct. 11, 1932 1,938,838 Jacobson Dec. 12, 1933 2,097,337 Oliver Oct. 26, 1937 2,392,540 Lyman Jan. 6, 1946 2,734,520 Abresch et al. Feb. 14, 1956 2,790,095 Peek et al. Apr. 23, 1957 FOREIGN PATENTS 518,166 Great Britain Feb. 20, 1940 

